MGP-79 submachine gun was developed during late 1970s by SIMA-CEFAR (Servicios Industriales de la Marina-Centro de Fabricacion de Armas), arms manufacturing branch of the Peruvian Navy. It was adopted for service by Peruvian Navy, Army and Police. Following initial experience, which showed certain design deficiencies (most notably, lack of any shoulder stock), during mid-1980s it was modified to MGP-79A version that featured side-folding shoulder stock. Since late eighties, MGP-79 was replaced in production by its further improved version, the MGP-87. It also has side-folding stock, shorter barrel and some other minor improvements.

MGP-79 submachine gun is a simple blowback weapon, firing from open bolt in semi- and full automatic modes. Fire mode selector lever is located on the left side, above the pistol grip; manual safety switch is placed behind the enlarged magazine housing, also on the left side of the gun. Feed is from detachable box magazines, compatible with Israeli UZI submachine guns. There is no shoulder stock on MGP-79; MGP-79A and MGP-87 feature side-folding shoulder stock, made of steel. Iron sights feature flip-up rear blade, with settings for 100 and 200 meters. Barrel is enclosed into removable perforated housing. MGP-87 has a modified barrel jacket that can be used to launch rifle grenades using special blank ammunition. Upon requirements, standard barrel also can be replaced with integrally silenced barrel.